Short- and long-term effects of a cardiac rehabilitation program in patients implanted with a left ventricular assist device

Abstract

The efficacy of cardiac rehabilitation in heart-failure patients who received a left-ventricular assist device (LVAD) instead of heart transplantation (HTx) is still unclear. This study aims to evaluate whether cardiac rehabilitation is beneficial in LVAD as HTx patients in the short term and whether its effects in LVAD patients persist over time. Twenty-five LVAD patients were evaluated by functional and psychological tests at admission (T0) and discharge (T1) of a 4-week inpatient structured rehabilitation program, and follow-ups 3 (T2), 6 (T3), and 12 months (T4) after discharge. Twenty-five matched HTx patients were also studied from T0 to T1 to compare the improvements in the six-minute walk test (6MWT). The quality-of-life scores substantially improved in LVAD patients and the 6MWT showed the same functional recovery as in HTx patients from T0 to T1. After T1, numerous LVAD patients withdrew from the study. However, the 6MWT outcome increased further from T1 to T3, with a positive trend during the follow-ups. Hemoglobin and the ventilatory performance increased, and the psychological perception of heart-failure symptoms and pain further improved at T2. In conclusion, exercise-based rehabilitation programs provide similar beneficial effects in LVAD and HTx patients, without deterioration in LVAD patients up to 12 months after discharge.

Fig 1. Timing, measures, and patients of the studies on the short-term efficacy of the cardiac rehabilitation (CR) program and long-term durability of its effects in patients implanted with a left ventricle assist device (LVAD).

The efficacy study is based on the outcomes of the six-minute walk test (6MWT), blood chemistry test (BloodT), psychological tests (PsychoT), and echocardiogram (Echo) at admission (T0) and discharge (T1) of the CR program in 25 LVAD patients; reference values are derived from a matched group of 25 heart transplant patients (HTx) who underwent the same CR program, selected from the Hospital database. The durability study is based on the outcomes of 6MWT, BloodT, PsychoT, Echo, and the cardiopulmonary exercise test (CPET) in the LVAD patients at T1 and follow-up visits three months (T2), six months (T3), and one year (T4) after discharge.

Fig 2. Distance walked during the six-minute walk test (6MWT) in patients who received the implant of a left ventricle assist device (LVAD, N = 25) or heart transplant (HTx, N = 25) at the start (T0) and end (T1) of the cardiac rehabilitation program.

Values as mean ±SD; the ** indicate significant differences between T0 and T1 at p<0.01 (Fisher’s LSD post-hoc analysis after repeated measures ANOVA).

Fig 3. LVAD patients: Box-and-whiskers plot representing the percent change of the distance walked during the six-minute walk test at the T2, T3, and T4 follow-ups compared with the reference value at hospital discharge (T1, dashed red line).

The whiskers show the maximum-minimum range, the box shows the first and third quartile, with the median; the label close to each box reports the median (interquartile range) values; the * indicates when the median value significantly differs from the reference at p<0.05.